Abstract: Objective The mortality rates are higher in children with lobar pneumonia,and the study on regimen is very important.This study aims to investigate the effect of adjuvant therapy with dexamethasone in children with lobar pneumonia,and its influence on the levels of inflammatory factors and ESR. Methods A total of 96 children with lobar pneumonia in our hospital from Jun,2015 to August,2016 were enrolled and divided into observation group (48 cases) and control group (48 cases).The two groups were given the conventional therapy including anti-inflammatory,cooling,antitussive and relieving asthma,and the observation group was additionally given adjuvant therapy with dexamethasone,with a dose of 0.2 mg/kg,1 time a day.The efficacy,levels of inflammatory factors and ESR before and after treatment were compared between the two groups. Results Total effective rate of the observation group (93.75%) was significantly higher than control group (70.83%) after the treatment (χ²=8.649,P<0.05);Clinical symptoms disappearing time and hospitalization time of the observation group was significantly lower than those in control group (t=-7.743,-8.073,-8.241,-4.112,P<0.05);The levels of TNF-α,IL-6,IL-8 and ESR were decreased significantly after the treatment in 2 groups (t_{observation group}=18.552,17.574,15.788,11.718,t_{control group}=10.500,11.085,11.979,6.315,P<0.05),and the observation group decreased more significantly than those in the control group (t=-13.250,-9.223,-9.161,-7.975,P<0.05). Conclusion Adjuvant therapy with dexamethasone has obvious effect on children with lobar pneumonia,which can obviously improve inflammation and ESR,relieve clinical symptoms,shorten hospitalization time.